\(D=1+3+3^2+...+3^{2027}\\ 3D=3+3^2+3^3+...+3^{2028}\\ 3D-D=\left(3+3^2+3^3+...+3^{2028}\right)-\left(1+3+3^2+...+3^{2027}\right)\\ 2D=3+3^2+3^3+....+3^{2028}-1-3-3^2-...-3^{2027}\\ 2D=3^{2028}-1\\ D=\dfrac{3^{2028}-1}{2}\)
Tìm X biết : \(\frac{x+1}{2014}+\frac{x+2}{2013}+\frac{x+3}{2012}+\frac{x+4}{2011}+\frac{x+2027}{3}=0\)
giúp mk vs
Cho đa thức f(x)=x^6 - 2014x^5 + 2014x^4 -2014x^3 + 2014x^2 - 2014x + 2027
Tính tổng
A=\(1^3+2^3+3^3+...+100^3\)
B=\(2^3+4^3+...+98^3\)
C=\(1^3+3^3+5^3+...+99^3\)
D=\(1^3-2^3+3^3-4^3+...+99^3-100^3\)
a) A= 32 . 1/243 . 812 .1/33
b) B= (4.25 ):(23 .1/6)
c) C= (-1/3)3 .(-1/3)2 .(-1/3)
d) D= (-1/3)-1 -(-6/7)0 +(1/2)2 :2
a,(3/7+1/2)2 b, (3/4-5/6)2 c,54.204 /255.45 d,(-105/3).(-64/5)
e,(1+2/3-1/4).(4/5-3/4)2 f 2:(1/2-2/3)3
Tìm x :
a, \(\dfrac{11}{12}\) - (\(\dfrac{2}{5}\) +x) = \(\dfrac{2}{3}\) b, x+\(\dfrac{2}{3}\) =\(\dfrac{3}{5}\) - \(\dfrac{-1}{6}\) c, x-[\(\dfrac{17}{2}\) -(\(\dfrac{-3}{7}\) + \(\dfrac{5}{3}\) )]=\(\dfrac{-1}{3}\)
d,\(\dfrac{9}{2}\) - [\(\dfrac{2}{3}\) - (x+\(\dfrac{7}{4}\) )] =\(\dfrac{-5}{4}\)
Mọi người giúp mình nha
Rút gọn các biểu thức sau:
a) 2x(2x-1)^2 - 3x(x+3)(x-3) - 4x(x+1)^2
b) (a-b+c)^2 - (b-c)^2 + 2ab-2ac
c) (3x+1)^2 - 2(3x+1)(3x+5) + (3x+5)^2
d) (3+1)(3^2+1)(3^4+1)(3^8+1)(3^16+1)(3^32+1)
e) (a+b-c)^2 + (a-b+c)^2 - 2(b-c)^2
g) (a+b+c)^2 + (a-b-c)^2 + (b-c-a)^2 + (c-a-b)^2
h) (a+b+c+d)^2 + (a+b-c-d)^2 + (a+c-b-d)^2 + (a+d-b-c)^2
Rút gọn các biểu thức sau:
a) 2x(2x-1)^2 - 3x(x+3)(x-3) - 4x(x+1)^2
b) (a-b+c)^2 - (b-c)^2 + 2ab-2ac
c) (3x+1)^2 - 2(3x+1)(3x+5) + (3x+5)^2
d) (3+1)(3^2+1)(3^4+1)(3^8+1)(3^16+1)(3^32+1)
e) (a+b-c)^2 + (a-b+c)^2 - 2(b-c)^2
g) (a+b+c)^2 + (a-b-c)^2 + (b-c-a)^2 + (c-a-b)^2
h) (a+b+c+d)^2 + (a+b-c-d)^2 + (a+c-b-d)^2 + (a+d-b-c)^2
cho a/b=c/d, chứng minh rằng:
a. ab/cd = a^2-b^2/ c^2 -d^2
b. 7a-4b/3a+5b=7c-4d/3c+5d
c. ac/bd= a^2+c^2/b^2+d^2= (c-a)^2/(d-b)^2
d. a^3+b^3/c^3+d^3= (a+b)^3/(c+d)^3 với (a/b =c/d khác 1)
D = 3^10 - 3^9 + 3^8 - 3^7 + ... + 3^2 - 3^1
